Re: [Patch, fortran PR89645/99065 No IMPLICIT type error with: ASSOCIATE( X => function() )

[Paul Richard Thomas <paul.richard.thomas@gmail.com>]

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Hi Harald,

Please find an updated version of the patch that rolls in Steve's patch for
PR114141, fixes unlimited polymorphic function selectors and cures the
memory leaks. I apologise for not working on this sooner but, as I informed
you, I have been away for an extended trip to Australia.

The chunks that fix PR114141 are picked out in comment 14 to the PR and the
cures to the problems that you found in the first review are found at
trans-stmt.cc:2047-49.

Regtests fine. OK for trunk, bearing in mind that most of the patch is ring
fenced by the inferred_type flag?

Cheers

Paul


On Mon, 8 Jan 2024 at 21:53, Harald Anlauf <anlauf@gmx.de> wrote:

> Hi Paul,
>
> your patch looks already very impressive!
>
> Regarding the patch as is, I am still trying to grok it, even with your
> explanations at hand...
>
> While the testcase works as advertised, I noticed that it exhibits a
> runtime memleak that occurs for (likely) each case where the associate
> target is an allocatable, class-valued function result.
>
> I tried to produce a minimal testcase using class(*), which apparently
> is not handled by your patch (it ICEs for me):
>
> program p
>    implicit none
>    class(*), allocatable :: x(:)
>    x = foo()
>    call prt (x)
>    deallocate (x)
>    ! up to here no memleak...
>    associate (var => foo())
>      call prt (var)
>    end associate
> contains
>    function foo() result(res)
>      class(*), allocatable :: res(:)
>      res = [42]
>    end function foo
>    subroutine prt (x)
>      class(*), intent(in) :: x(:)
>      select type (x)
>      type is (integer)
>         print *, x
>      class default
>         stop 99
>      end select
>    end subroutine prt
> end
>
> Traceback (truncated):
>
> foo.f90:9:18:
>
>      9 |     call prt (var)
>        |                  1
> internal compiler error: tree check: expected record_type or union_type
> or qual_union_type, have function_type in gfc_class_len_get, at
> fortran/trans-expr.cc:271
> 0x19fd5d5 tree_check_failed(tree_node const*, char const*, int, char
> const*, ...)
>          ../../gcc-trunk/gcc/tree.cc:8952
> 0xe1562d tree_check3(tree_node*, char const*, int, char const*,
> tree_code, tree_code, tree_code)
>          ../../gcc-trunk/gcc/tree.h:3652
> 0xe3e264 gfc_class_len_get(tree_node*)
>          ../../gcc-trunk/gcc/fortran/trans-expr.cc:271
> 0xecda48 trans_associate_var
>          ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2325
> 0xecdd09 gfc_trans_block_construct(gfc_code*)
>          ../../gcc-trunk/gcc/fortran/trans-stmt.cc:2383
> [...]
>
> I don't see anything wrong with it: NAG groks it, like Nvidia and Flang,
> while Intel crashes at runtime.
>
> Can you have another brief look?
>
> Thanks,
> Harald
>
>
> On 1/6/24 18:26, Paul Richard Thomas wrote:
> > These PRs come about because of gfortran's single pass parsing. If the
> > function in the title is parsed after the associate construct, then its
> > type and rank are not known. The point at which this becomes a problem is
> > when expressions within the associate block are parsed. primary.cc
> > (gfc_match_varspec) could already deal with intrinsic types and so
> > component references were the trigger for the problem.
> >
> > The two major parts of this patch are the fixup needed in
> gfc_match_varspec
> > and the resolution of  expressions with references in resolve.cc
> > (gfc_fixup_inferred_type_refs). The former relies on the two new
> functions
> > in symbol.cc to search for derived types with an appropriate component to
> > match the component reference and then set the associate name to have a
> > matching derived type. gfc_fixup_inferred_type_refs is called in
> resolution
> > and so the type of the selector function is known.
> > gfc_fixup_inferred_type_refs ensures that the component references use
> this
> > derived type and that array references occur in the right place in
> > expressions and match preceding array specs. Most of the work in
> preparing
> > the patch was sorting out cases where the selector was not a derived type
> > but, instead, a class function. If it were not for this, the patch would
> > have been submitted six months ago :-(
> >
> > The patch is relatively safe because most of the chunks are guarded by
> > testing for the associate name being an inferred type, which is set in
> > gfc_match_varspec. For this reason, I do not think it likely that the
> patch
> > will cause regressions. However, it is more than possible that variants
> not
> > appearing in the submitted testcase will throw up new bugs.
> >
> > Jerry has already given the patch a whirl and found that it applies
> > cleanly, regtests OK and works as advertised.
> >
> > OK for trunk?
> >
> > Paul
> ...snip...

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diff --git a/gcc/fortran/class.cc b/gcc/fortran/class.cc
index ce31a93abcd..abe89630be3 100644
--- a/gcc/fortran/class.cc
+++ b/gcc/fortran/class.cc
@@ -815,6 +815,56 @@ gfc_build_class_symbol (gfc_typespec *ts, symbol_attribute *attr,
 }
 
 
+/* Change class, using gfc_build_class_symbol. This is needed for associate
+   names, when rank changes or a derived type is produced by resolution.  */
+
+void
+gfc_change_class (gfc_typespec *ts, symbol_attribute *sym_attr,
+		  gfc_array_spec *sym_as, int rank, int corank)
+{
+  symbol_attribute attr;
+  gfc_component *c;
+  gfc_array_spec *as = NULL;
+  gfc_symbol *der = ts->u.derived;
+
+  ts->type = BT_CLASS;
+  attr = *sym_attr;
+  attr.class_ok = 0;
+  attr.associate_var = 1;
+  attr.class_pointer = 1;
+  attr.allocatable = 0;
+  attr.pointer = 1;
+  attr.dimension = rank ? 1 : 0;
+  if (rank)
+    {
+      if (sym_as)
+	as = gfc_copy_array_spec (sym_as);
+      else
+	{
+	  as = gfc_get_array_spec ();
+	  as->rank = rank;
+	  as->type = AS_DEFERRED;
+	  as->corank = corank;
+	}
+    }
+  if (as && as->corank != 0)
+    attr.codimension = 1;
+
+  if (!gfc_build_class_symbol (ts, &attr, &as))
+    gcc_unreachable ();
+
+  gfc_set_sym_referenced (ts->u.derived);
+
+  /* Make sure the _vptr is set.  */
+  c = gfc_find_component (ts->u.derived, "_vptr", true, true, NULL);
+  if (c->ts.u.derived == NULL)
+    c->ts.u.derived = gfc_find_derived_vtab (der);
+  /* _vptr now has the _vtab in it, change it to the _vtype.  */
+  if (c->ts.u.derived->attr.vtab)
+    c->ts.u.derived = c->ts.u.derived->ts.u.derived;
+}
+
+
 /* Add a procedure pointer component to the vtype
    to represent a specific type-bound procedure.  */
 
diff --git a/gcc/fortran/dump-parse-tree.cc b/gcc/fortran/dump-parse-tree.cc
index 7b154eb3ca7..99b577c91c4 100644
--- a/gcc/fortran/dump-parse-tree.cc
+++ b/gcc/fortran/dump-parse-tree.cc
@@ -2692,11 +2692,20 @@ show_code_node (int level, gfc_code *c)
 
     case EXEC_BLOCK:
       {
-	const char* blocktype;
+	const char *blocktype, *sname = NULL;
 	gfc_namespace *saved_ns;
 	gfc_association_list *alist;
 
-	if (c->ext.block.assoc)
+	if (c->ext.block.ns && c->ext.block.ns->code
+	    && c->ext.block.ns->code->op == EXEC_SELECT_TYPE)
+	  {
+	    gfc_expr *fcn = c->ext.block.ns->code->expr1;
+	    blocktype = "SELECT TYPE";
+	    /* expr1 is _loc(assoc_name->vptr)  */
+	    if (fcn && fcn->expr_type == EXPR_FUNCTION)
+	      sname = fcn->value.function.actual->expr->symtree->n.sym->name;
+	  }
+	else if (c->ext.block.assoc)
 	  blocktype = "ASSOCIATE";
 	else
 	  blocktype = "BLOCK";
@@ -2704,7 +2713,7 @@ show_code_node (int level, gfc_code *c)
 	fprintf (dumpfile, "%s ", blocktype);
 	for (alist = c->ext.block.assoc; alist; alist = alist->next)
 	  {
-	    fprintf (dumpfile, " %s = ", alist->name);
+	    fprintf (dumpfile, " %s = ", sname ? sname : alist->name);
 	    show_expr (alist->target);
 	  }
 
@@ -2735,7 +2744,7 @@ show_code_node (int level, gfc_code *c)
       if (c->op == EXEC_SELECT_RANK)
 	fputs ("SELECT RANK ", dumpfile);
       else if (c->op == EXEC_SELECT_TYPE)
-	fputs ("SELECT TYPE ", dumpfile);
+	fputs ("SELECT CASE ", dumpfile); // Preceded by SELECT TYPE construct
       else
 	fputs ("SELECT CASE ", dumpfile);
       show_expr (c->expr1);
diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index ebba2336e12..70b9faad074 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -2963,6 +2963,11 @@ typedef struct gfc_association_list
   locus where;
 
   gfc_expr *target;
+
+  /* Used for inferring the derived type of an associate name, whose selector
+     is a sibling derived type function that has not yet been parsed.  */
+  gfc_symbol *derived_types;
+  unsigned inferred_type:1;
 }
 gfc_association_list;
 #define gfc_get_association_list() XCNEW (gfc_association_list)
@@ -3529,6 +3534,7 @@ bool gfc_add_component (gfc_symbol *, const char *, gfc_component **);
 gfc_symbol *gfc_use_derived (gfc_symbol *);
 gfc_component *gfc_find_component (gfc_symbol *, const char *, bool, bool,
                                    gfc_ref **);
+int gfc_find_derived_types (gfc_symbol *, gfc_namespace *, const char *);
 
 gfc_st_label *gfc_get_st_label (int);
 void gfc_free_st_label (gfc_st_label *);
@@ -3795,6 +3801,7 @@ void gfc_free_association_list (gfc_association_list *);
 void gfc_expression_rank (gfc_expr *);
 bool gfc_op_rank_conformable (gfc_expr *, gfc_expr *);
 bool gfc_resolve_ref (gfc_expr *);
+void gfc_fixup_inferred_type_refs (gfc_expr *);
 bool gfc_resolve_expr (gfc_expr *);
 void gfc_resolve (gfc_namespace *);
 void gfc_resolve_code (gfc_code *, gfc_namespace *);
@@ -3988,6 +3995,8 @@ unsigned int gfc_hash_value (gfc_symbol *);
 gfc_expr *gfc_get_len_component (gfc_expr *e, int);
 bool gfc_build_class_symbol (gfc_typespec *, symbol_attribute *,
 			     gfc_array_spec **);
+void gfc_change_class (gfc_typespec *, symbol_attribute *,
+		       gfc_array_spec *, int, int);
 gfc_symbol *gfc_find_derived_vtab (gfc_symbol *);
 gfc_symbol *gfc_find_vtab (gfc_typespec *);
 gfc_symtree* gfc_find_typebound_proc (gfc_symbol*, bool*,
@@ -4018,6 +4027,10 @@ bool gfc_may_be_finalized (gfc_typespec);
 #define IS_PROC_POINTER(sym) \
 	(sym->ts.type == BT_CLASS && sym->attr.class_ok && CLASS_DATA (sym) \
 	 ? CLASS_DATA (sym)->attr.proc_pointer : sym->attr.proc_pointer)
+#define IS_INFERRED_TYPE(expr) \
+	(expr && expr->expr_type == EXPR_VARIABLE \
+	 && expr->symtree->n.sym->assoc \
+	 && expr->symtree->n.sym->assoc->inferred_type)
 
 /* frontend-passes.cc */
 
diff --git a/gcc/fortran/match.cc b/gcc/fortran/match.cc
index eee569dac91..64f61c50c66 100644
--- a/gcc/fortran/match.cc
+++ b/gcc/fortran/match.cc
@@ -1963,6 +1963,20 @@ gfc_match_associate (void)
 	  goto assocListError;
 	}
 
+      /* If the selector expression is enclosed in parentheses and the
+	 expression is not a variable, throw the parentheses away.  */
+      while (newAssoc->target->expr_type == EXPR_OP
+	     && newAssoc->target->value.op.op == INTRINSIC_PARENTHESES)
+	{
+	  if (newAssoc->target->value.op.op1->expr_type == EXPR_VARIABLE)
+	    break;
+	  else
+	    {
+	      gfc_expr *e = gfc_copy_expr (newAssoc->target->value.op.op1);
+	      gfc_replace_expr (newAssoc->target, e);
+	    }
+	}
+
       /* The `variable' field is left blank for now; because the target is not
 	 yet resolved, we can't use gfc_has_vector_subscript to determine it
 	 for now.  This is set during resolution.  */
@@ -6322,7 +6336,8 @@ gfc_match_select (void)
 /* Transfer the selector typespec to the associate name.  */
 
 static void
-copy_ts_from_selector_to_associate (gfc_expr *associate, gfc_expr *selector)
+copy_ts_from_selector_to_associate (gfc_expr *associate, gfc_expr *selector,
+				    bool select_type = false)
 {
   gfc_ref *ref;
   gfc_symbol *assoc_sym;
@@ -6405,12 +6420,30 @@ copy_ts_from_selector_to_associate (gfc_expr *associate, gfc_expr *selector)
     assoc_sym->as = NULL;
 
 build_class_sym:
-  if (selector->ts.type == BT_CLASS)
+  /* Deal with the very specific case of a SELECT_TYPE selector being an
+     associate_name whose type has been identified by component references.
+     It must be assumed that it will be identified as a CLASS expression,
+     so convert it now.  */
+  if (select_type
+      && IS_INFERRED_TYPE (selector)
+      && selector->ts.type == BT_DERIVED)
+    {
+      gfc_find_derived_vtab (selector->ts.u.derived);
+      /* The correct class container has to be available.  */
+      assoc_sym->ts.u.derived = selector->ts.u.derived;
+      assoc_sym->ts.type = BT_CLASS;
+      assoc_sym->attr.pointer = 1;
+      if (!selector->ts.u.derived->attr.is_class)
+	gfc_build_class_symbol (&assoc_sym->ts, &assoc_sym->attr, &assoc_sym->as);
+      associate->ts = assoc_sym->ts;
+    }
+  else if (selector->ts.type == BT_CLASS)
     {
       /* The correct class container has to be available.  */
       assoc_sym->ts.type = BT_CLASS;
       assoc_sym->ts.u.derived = CLASS_DATA (selector)
-	? CLASS_DATA (selector)->ts.u.derived : selector->ts.u.derived;
+				? CLASS_DATA (selector)->ts.u.derived
+				: selector->ts.u.derived;
       assoc_sym->attr.pointer = 1;
       gfc_build_class_symbol (&assoc_sym->ts, &assoc_sym->attr, &assoc_sym->as);
     }
@@ -6438,7 +6471,7 @@ build_associate_name (const char *name, gfc_expr **e1, gfc_expr **e2)
   if (expr2->ts.type == BT_UNKNOWN)
     sym->attr.untyped = 1;
   else
-    copy_ts_from_selector_to_associate (expr1, expr2);
+    copy_ts_from_selector_to_associate (expr1, expr2, true);
 
   sym->attr.flavor = FL_VARIABLE;
   sym->attr.referenced = 1;
diff --git a/gcc/fortran/parse.cc b/gcc/fortran/parse.cc
index a4fda6e5eb6..a2bf328f681 100644
--- a/gcc/fortran/parse.cc
+++ b/gcc/fortran/parse.cc
@@ -5150,6 +5150,17 @@ parse_associate (void)
       sym->declared_at = a->where;
       gfc_set_sym_referenced (sym);
 
+      /* If the selector is a inferred type then the associate_name had better
+	 be as well. Use array references, if present, to identify it as an
+	 array.  */
+      if (IS_INFERRED_TYPE (a->target))
+	{
+	  sym->assoc->inferred_type = 1;
+	  for (gfc_ref *r = a->target->ref; r; r = r->next)
+	    if (r->type == REF_ARRAY)
+	      sym->attr.dimension = 1;
+	}
+
       /* Initialize the typespec.  It is not available in all cases,
 	 however, as it may only be set on the target during resolution.
 	 Still, sometimes it helps to have it right now -- especially
@@ -5176,21 +5187,41 @@ parse_associate (void)
 	       && sym->ts.u.cl->length->expr_type == EXPR_CONSTANT))
 	sym->ts.u.cl = gfc_new_charlen (gfc_current_ns, NULL);
 
+      /* If the function has been parsed, go straight to the result to
+	 obtain the expression rank.  */
+      if (target->expr_type == EXPR_FUNCTION
+	  && target->symtree
+	  && target->symtree->n.sym)
+	{
+	  tsym = target->symtree->n.sym;
+	  if (!tsym->result)
+	    tsym->result = tsym;
+	  sym->ts = tsym->result->ts;
+	  if (sym->ts.type == BT_CLASS)
+	    {
+	      if (CLASS_DATA (sym)->as)
+		target->rank = CLASS_DATA (sym)->as->rank;
+	      sym->attr.class_ok = 1;
+	    }
+	  else
+	    target->rank = tsym->result->as ? tsym->result->as->rank : 0;
+	}
+
       /* Check if the target expression is array valued. This cannot be done
 	 by calling gfc_resolve_expr because the context is unavailable.
 	 However, the references can be resolved and the rank of the target
 	 expression set.  */
-      if (target->ref && gfc_resolve_ref (target)
+      if (!sym->assoc->inferred_type
+	  && target->ref && gfc_resolve_ref (target)
 	  && target->expr_type != EXPR_ARRAY
 	  && target->expr_type != EXPR_COMPCALL)
 	gfc_expression_rank (target);
 
       /* Determine whether or not function expressions with unknown type are
 	 structure constructors. If so, the function result can be converted
-	 to be a derived type.
-	 TODO: Deal with references to sibling functions that have not yet been
-	 parsed (PRs 89645 and 99065).  */
-      if (target->expr_type == EXPR_FUNCTION && target->ts.type == BT_UNKNOWN)
+	 to be a derived type.  */
+      if (target->expr_type == EXPR_FUNCTION
+	  && target->ts.type == BT_UNKNOWN)
 	{
 	  gfc_symbol *derived;
 	  /* The derived type has a leading uppercase character.  */
@@ -5200,16 +5231,7 @@ parse_associate (void)
 	    {
 	      sym->ts.type = BT_DERIVED;
 	      sym->ts.u.derived = derived;
-	    }
-	  else if (target->symtree && (tsym = target->symtree->n.sym))
-	    {
-	      sym->ts = tsym->result ? tsym->result->ts : tsym->ts;
-	      if (sym->ts.type == BT_CLASS)
-		{
-		  if (CLASS_DATA (sym)->as)
-		    target->rank = CLASS_DATA (sym)->as->rank;
-		  sym->attr.class_ok = 1;
-		}
+	      sym->assoc->inferred_type = 0;
 	    }
 	}
 
diff --git a/gcc/fortran/primary.cc b/gcc/fortran/primary.cc
index 12e7bf3c873..c64ebf67c70 100644
--- a/gcc/fortran/primary.cc
+++ b/gcc/fortran/primary.cc
@@ -2057,6 +2057,7 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
   bool unknown;
   bool inquiry;
   bool intrinsic;
+  bool inferred_type;
   locus old_loc;
   char sep;
 
@@ -2087,6 +2088,18 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
   if (sym->assoc && sym->assoc->target)
     tgt_expr = sym->assoc->target;
 
+  inferred_type = IS_INFERRED_TYPE (primary);
+
+  /* SELECT TYPE and SELECT RANK temporaries within an ASSOCIATE block, whose
+     selector has not been parsed, can generate errors with array and component
+     refs.. Use 'inferred_type' as a flag to suppress these errors.  */
+  if (!inferred_type
+      && (gfc_peek_ascii_char () == '(' && !sym->attr.dimension)
+      && !sym->attr.codimension
+      && sym->attr.select_type_temporary
+      && !sym->attr.select_rank_temporary)
+    inferred_type = true;
+
   /* For associate names, we may not yet know whether they are arrays or not.
      If the selector expression is unambiguously an array; eg. a full array
      or an array section, then the associate name must be an array and we can
@@ -2136,7 +2149,8 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
 	sym->ts.u.derived = tgt_expr->ts.u.derived;
     }
 
-  if ((equiv_flag && gfc_peek_ascii_char () == '(')
+  if ((inferred_type && !sym->as && gfc_peek_ascii_char () == '(')
+      || (equiv_flag && gfc_peek_ascii_char () == '(')
       || gfc_peek_ascii_char () == '[' || sym->attr.codimension
       || (sym->attr.dimension && sym->ts.type != BT_CLASS
 	  && !sym->attr.proc_pointer && !gfc_is_proc_ptr_comp (primary)
@@ -2194,7 +2208,7 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
   inquiry = false;
   if (m == MATCH_YES && sep == '%'
       && primary->ts.type != BT_CLASS
-      && primary->ts.type != BT_DERIVED)
+      && (primary->ts.type != BT_DERIVED || inferred_type))
     {
       match mm;
       old_loc = gfc_current_locus;
@@ -2209,7 +2223,8 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
     gfc_set_default_type (sym, 0, sym->ns);
 
   /* See if there is a usable typespec in the "no IMPLICIT type" error.  */
-  if (sym->ts.type == BT_UNKNOWN && m == MATCH_YES)
+  if ((sym->ts.type == BT_UNKNOWN || inferred_type)
+      && m == MATCH_YES)
     {
       bool permissible;
 
@@ -2220,7 +2235,8 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
 			|| tgt_expr->symtree->n.sym->attr.if_source
 								== IFSRC_DECL);
       permissible = permissible
-		    || (tgt_expr && tgt_expr->expr_type == EXPR_OP);
+		    || (tgt_expr && (tgt_expr->expr_type == EXPR_OP
+			|| (inquiry && tgt_expr->expr_type == EXPR_FUNCTION)));
 
       if (permissible)
 	{
@@ -2228,6 +2244,31 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
 	  sym->ts = tgt_expr->ts;
 	}
 
+      /* If this hasn't done the trick and the target expression is a function,
+	 then this must be a derived type if 'name' matches an accessible type
+	 both in this namespace and the as yet unparsed sibling function.  */
+      if (tgt_expr && tgt_expr->expr_type == EXPR_FUNCTION
+	  && (sym->ts.type == BT_UNKNOWN || inferred_type)
+	  && gfc_find_derived_types (sym, gfc_current_ns, name))
+	{
+	  sym->assoc->inferred_type = 1;
+	  /* The first returned type is as good as any at this stage.  */
+	  gfc_symbol **dts = &sym->assoc->derived_types;
+	  tgt_expr->ts.type = BT_DERIVED;
+	  tgt_expr->ts.kind = 0;
+	  tgt_expr->ts.u.derived = *dts;
+	  sym->ts = tgt_expr->ts;
+	  /* Delete the dt list to prevent interference with trans-type.cc's
+	     treatment of derived type decls, even if this process has to be
+	     done again for another primary expression.  */
+	  while (*dts && (*dts)->dt_next)
+	    {
+	      gfc_symbol **tmp = &(*dts)->dt_next;
+	      *dts = NULL;
+	      dts = tmp;
+	    }
+	}
+
       if (sym->ts.type == BT_UNKNOWN)
 	{
 	  gfc_error ("Symbol %qs at %C has no IMPLICIT type", sym->name);
@@ -2294,6 +2335,17 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
 		      break;
 		    }
 
+		  /* With 'associate(x => sin(cmplx(1,0)))', gfortran gets here
+		     with an unknown type-spec for primary, but it can be
+		     gleaned from the associate target.  */
+		  if ((tmp->u.i == INQUIRY_RE || tmp->u.i == INQUIRY_IM)
+		      && primary->ts.type == BT_UNKNOWN
+		      && primary->symtree && primary->symtree->n.sym
+		      && primary->symtree->n.sym->assoc
+		      && primary->symtree->n.sym->assoc->target
+		      && primary->symtree->n.sym->assoc->target->ts.type == BT_COMPLEX)
+		    primary->ts = primary->symtree->n.sym->assoc->target->ts;
+
 		  if ((tmp->u.i == INQUIRY_RE || tmp->u.i == INQUIRY_IM)
 		      && primary->ts.type != BT_COMPLEX)
 		    {
diff --git a/gcc/fortran/resolve.cc b/gcc/fortran/resolve.cc
index 02acc4aef31..3f48ec34932 100644
--- a/gcc/fortran/resolve.cc
+++ b/gcc/fortran/resolve.cc
@@ -5866,6 +5866,13 @@ resolve_variable (gfc_expr *e)
       return false;
     }
 
+  /* Guessed type variables are associate_names whose selector had not been
+     parsed at the time that the construct was parsed. Now the namespace is
+     being resolved, the TKR of the selector will be available for fixup of
+     the associate_name.  */
+  if (IS_INFERRED_TYPE (e) && e->ref)
+    gfc_fixup_inferred_type_refs (e);
+
   /* For variables that are used in an associate (target => object) where
      the object's basetype is array valued while the target is scalar,
      the ts' type of the component refs is still array valued, which
@@ -6171,6 +6178,115 @@ resolve_procedure:
 }
 
 
+/* 'sym' was initially guessed to be derived type but has been corrected
+   in resolve_assoc_var to be a class entity or the derived type correcting.
+   If a class entity it will certainly need the _data reference or the
+   reference derived type symbol correcting in the first component ref if
+   a derived type.  */
+
+void
+gfc_fixup_inferred_type_refs (gfc_expr *e)
+{
+  gfc_ref *ref;
+  gfc_symbol *sym, *derived;
+  gfc_expr *target;
+  sym = e->symtree->n.sym;
+
+  /* This is an associate_name whose selector is a component ref of a selector
+     that is a inferred type associate_name.  */
+  if (sym->ts.type != BT_DERIVED && sym->ts.type != BT_CLASS)
+    {
+      e->rank = sym->as ? sym->as->rank : 0;
+      sym->attr.dimension = e->rank ? 1 : 0;
+      if (!e->rank && e->ref->type == REF_ARRAY)
+	{
+	  ref = e->ref;
+	  e->ref = ref->next;
+	  free (ref);
+	}
+      return;
+    }
+
+  derived = sym->ts.type == BT_CLASS ? CLASS_DATA (sym)->ts.u.derived
+				     : sym->ts.u.derived;
+
+  /* Ensure that class symbols have an array spec and ensure that there
+     is a _data field reference following class type references.  */
+  if (sym->ts.type == BT_CLASS
+      && sym->assoc->target->ts.type == BT_CLASS)
+    {
+      e->rank = CLASS_DATA (sym)->as ? CLASS_DATA (sym)->as->rank : 0;
+      sym->attr.dimension = 0;
+      CLASS_DATA (sym)->attr.dimension = e->rank ? 1 : 0;
+      if (e->ref && (e->ref->type != REF_COMPONENT
+		     || e->ref->u.c.component->name[0] != '_'))
+	{
+	  ref = gfc_get_ref ();
+	  ref->type = REF_COMPONENT;
+	  ref->next = e->ref;
+	  e->ref = ref;
+	  ref->u.c.component = gfc_find_component (sym->ts.u.derived, "_data",
+						   true, true, NULL);
+	  ref->u.c.sym = sym->ts.u.derived;
+	}
+    }
+
+  /* Proceed as far as the first component reference and ensure that the
+     correct derived type is being used.  */
+  for (ref = e->ref; ref; ref = ref->next)
+    if (ref->type == REF_COMPONENT)
+      {
+	if (ref->u.c.component->name[0] != '_')
+	  ref->u.c.sym = derived;
+	else
+	  ref->u.c.sym = sym->ts.u.derived;
+	break;
+      }
+
+  /* Verify that the type inferrence mechanism has not introduced a spurious
+     array reference.  This can happen with an associate name, whose selector
+     is an element of another inferred type.  */
+  target = e->symtree->n.sym->assoc->target;
+  if (!(sym->ts.type == BT_CLASS ? CLASS_DATA (sym)->as : sym->as)
+      && e != target && !target->rank)
+    {
+      /* First case: array ref after the scalar class or derived associate_name.  */
+      if (e->ref && e->ref->type == REF_ARRAY
+	  && e->ref->u.ar.type != AR_ELEMENT)
+	{
+	  ref = e->ref;
+	  e->ref = ref->next;
+	  free (ref);
+
+	  /* If it hasn't a ref to the '_data' field supply one.  */
+	  if (sym->ts.type == BT_CLASS
+	      && !(e->ref->type == REF_COMPONENT
+		   && strcmp (e->ref->u.c.component->name, "_data")))
+	    {
+	      gfc_ref *new_ref;
+	      gfc_find_component (e->symtree->n.sym->ts.u.derived,
+				  "_data", true, true, &new_ref);
+	      new_ref->next = e->ref;
+	      e->ref = new_ref;
+	    }
+	}
+      /* 2nd case: a ref to the '_data' field followed by an array ref.  */
+      else if (e->ref && e->ref->type == REF_COMPONENT
+	       && strcmp (e->ref->u.c.component->name, "_data") == 0
+	       && e->ref->next && e->ref->next->type == REF_ARRAY
+	       && e->ref->next->u.ar.type != AR_ELEMENT)
+	{
+	  ref = e->ref->next;
+	  e->ref->next = e->ref->next->next;
+	  free (ref);
+	}
+    }
+
+  /* Now that all the references are OK, get the expression rank.  */
+  gfc_expression_rank (e);
+}
+
+
 /* Checks to see that the correct symbol has been host associated.
    The only situations where this arises are:
 	(i)  That in which a twice contained function is parsed after
@@ -9263,6 +9379,46 @@ resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
       return;
     }
 
+  if (sym->assoc->inferred_type || IS_INFERRED_TYPE (target))
+    {
+      symbol_attribute attr;
+
+      /* By now, the type of the target has been fixed up.  */
+      if (sym->ts.type == BT_DERIVED
+	  && target->ts.type == BT_CLASS
+	  && !UNLIMITED_POLY (target))
+	{
+	  sym->ts = CLASS_DATA (target)->ts;
+	  if (!sym->as)
+	    sym->as = gfc_copy_array_spec (CLASS_DATA (target)->as);
+	  attr = CLASS_DATA (sym) ? CLASS_DATA (sym)->attr : sym->attr;
+	  sym->attr.dimension = target->rank ? 1 : 0;
+	  gfc_change_class (&sym->ts, &attr, sym->as,
+			    target->rank, gfc_get_corank (target));
+	  sym->as = NULL;
+	}
+      else if (target->ts.type == BT_DERIVED
+	       && target->symtree->n.sym->ts.type == BT_CLASS
+	       && IS_INFERRED_TYPE (target)
+	       && target->ref && target->ref->next
+	       && target->ref->next->type == REF_ARRAY
+	       && !target->ref->next->next)
+	{
+	  sym->ts = target->ts;
+	  attr = CLASS_DATA (sym) ? CLASS_DATA (sym)->attr : sym->attr;
+	  sym->attr.dimension = target->rank ? 1 : 0;
+	  gfc_change_class (&sym->ts, &attr, sym->as,
+			    target->rank, gfc_get_corank (target));
+	  sym->as = NULL;
+	  target->ts = sym->ts;
+	}
+      else if ((target->ts.type == BT_DERIVED)
+	       || (sym->ts.type == BT_CLASS && target->ts.type == BT_CLASS
+		   && CLASS_DATA (target)->as && !CLASS_DATA (sym)->as))
+	sym->ts = target->ts;
+    }
+
+
   if (target->expr_type == EXPR_NULL)
     {
       gfc_error ("Selector at %L cannot be NULL()", &target->where);
@@ -9289,15 +9445,50 @@ resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 			  || gfc_is_ptr_fcn (target));
 
   /* Finally resolve if this is an array or not.  */
+  if (target->expr_type == EXPR_FUNCTION
+      && (sym->ts.type == BT_CLASS || sym->ts.type == BT_DERIVED))
+    {
+      gfc_expression_rank (target);
+      if (target->ts.type == BT_DERIVED
+	  && !sym->as
+	  && target->symtree->n.sym->as)
+	{
+	  sym->as = gfc_copy_array_spec (target->symtree->n.sym->as);
+	  sym->attr.dimension = 1;
+	}
+      else if (target->ts.type == BT_CLASS
+	       && CLASS_DATA (target)->as)
+	{
+	  target->rank = CLASS_DATA (target)->as->rank;
+	  if (!(sym->ts.type == BT_CLASS && CLASS_DATA (sym)->as))
+	    {
+	      sym->ts = target->ts;
+	      sym->attr.dimension = 0;
+	    }
+	}
+    }
+
+
   if (sym->attr.dimension && target->rank == 0)
     {
       /* primary.cc makes the assumption that a reference to an associate
 	 name followed by a left parenthesis is an array reference.  */
-      if (sym->ts.type != BT_CHARACTER)
-	gfc_error ("Associate-name %qs at %L is used as array",
-		   sym->name, &sym->declared_at);
-      sym->attr.dimension = 0;
-      return;
+      if (sym->assoc->inferred_type && sym->ts.type != BT_CLASS)
+	{
+	  gfc_expression_rank (sym->assoc->target);
+	  sym->attr.dimension = sym->assoc->target->rank ? 1 : 0;
+	  if (!sym->attr.dimension && sym->as)
+	    sym->as = NULL;
+	}
+
+      if (sym->attr.dimension && target->rank == 0)
+	{
+	  if (sym->ts.type != BT_CHARACTER)
+	    gfc_error ("Associate-name %qs at %L is used as array",
+		       sym->name, &sym->declared_at);
+	  sym->attr.dimension = 0;
+	  return;
+	}
     }
 
   /* We cannot deal with class selectors that need temporaries.  */
@@ -9356,7 +9547,7 @@ resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 	     correct this now.  */
 	  gfc_typespec *ts = &target->ts;
 	  gfc_ref *ref;
-	  gfc_component *c;
+
 	  for (ref = target->ref; ref != NULL; ref = ref->next)
 	    {
 	      switch (ref->type)
@@ -9374,32 +9565,15 @@ resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 	    }
 	  /* Create a scalar instance of the current class type.  Because the
 	     rank of a class array goes into its name, the type has to be
-	     rebuild.  The alternative of (re-)setting just the attributes
+	     rebuilt.  The alternative of (re-)setting just the attributes
 	     and as in the current type, destroys the type also in other
 	     places.  */
 	  as = NULL;
 	  sym->ts = *ts;
 	  sym->ts.type = BT_CLASS;
 	  attr = CLASS_DATA (sym) ? CLASS_DATA (sym)->attr : sym->attr;
-	  attr.class_ok = 0;
-	  attr.associate_var = 1;
-	  attr.dimension = attr.codimension = 0;
-	  attr.class_pointer = 1;
-	  if (!gfc_build_class_symbol (&sym->ts, &attr, &as))
-	    gcc_unreachable ();
-	  /* Make sure the _vptr is set.  */
-	  c = gfc_find_component (sym->ts.u.derived, "_vptr", true, true, NULL);
-	  if (c->ts.u.derived == NULL)
-	    c->ts.u.derived = gfc_find_derived_vtab (sym->ts.u.derived);
-	  CLASS_DATA (sym)->attr.pointer = 1;
-	  CLASS_DATA (sym)->attr.class_pointer = 1;
-	  gfc_set_sym_referenced (sym->ts.u.derived);
-	  gfc_commit_symbol (sym->ts.u.derived);
-	  /* _vptr now has the _vtab in it, change it to the _vtype.  */
-	  if (c->ts.u.derived->attr.vtab)
-	    c->ts.u.derived = c->ts.u.derived->ts.u.derived;
-	  c->ts.u.derived->ns->types_resolved = 0;
-	  resolve_types (c->ts.u.derived->ns);
+	  gfc_change_class (&sym->ts, &attr, as, 0, 0);
+	  sym->as = NULL;
 	}
     }
 
@@ -9443,6 +9617,14 @@ resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 	}
     }
 
+  if (sym->ts.type == BT_CLASS
+      && IS_INFERRED_TYPE (target)
+      && target->ts.type == BT_DERIVED
+      && CLASS_DATA (sym)->ts.u.derived == target->ts.u.derived
+      && target->ref && target->ref->next
+      && target->ref->next->type == REF_ARRAY)
+    target->ts = target->symtree->n.sym->ts;
+
   /* If the target is a good class object, so is the associate variable.  */
   if (sym->ts.type == BT_CLASS && gfc_expr_attr (target).class_ok)
     sym->attr.class_ok = 1;
diff --git a/gcc/fortran/symbol.cc b/gcc/fortran/symbol.cc
index 5d9852c79e0..6d8cdf39f94 100644
--- a/gcc/fortran/symbol.cc
+++ b/gcc/fortran/symbol.cc
@@ -291,6 +291,19 @@ bool
 gfc_set_default_type (gfc_symbol *sym, int error_flag, gfc_namespace *ns)
 {
   gfc_typespec *ts;
+  gfc_expr *e;
+
+  /* Check to see if a function selector of unknown type can be resolved.  */
+  if (sym->assoc
+      && (e = sym->assoc->target)
+      && e->expr_type == EXPR_FUNCTION)
+    {
+      if (e->ts.type == BT_UNKNOWN)
+	gfc_resolve_expr (e);
+      sym->ts = e->ts;
+      if (sym->ts.type != BT_UNKNOWN)
+	return true;
+    }
 
   if (sym->ts.type != BT_UNKNOWN)
     gfc_internal_error ("gfc_set_default_type(): symbol already has a type");
@@ -307,7 +320,7 @@ gfc_set_default_type (gfc_symbol *sym, int error_flag, gfc_namespace *ns)
 		       "; did you mean %qs?",
 		       sym->name, &sym->declared_at, guessed);
 	  else
-	    gfc_error ("Symbol %qs at %L has no IMPLICIT type",
+	    gfc_error ("Symbol %qs at %L has no IMPLICIT type(symbol)",
 		       sym->name, &sym->declared_at);
 	  sym->attr.untyped = 1; /* Ensure we only give an error once.  */
 	}
@@ -2402,6 +2415,66 @@ bad:
 }
 
 
+/* Find all derived types in the uppermost namespace that have a component
+   a component called name and stash them in the assoc field of an
+   associate name variable.
+   This is used to infer the derived type of an associate name, whose selector
+   is a sibling derived type function that has not yet been parsed. Either
+   the derived type is use associated in both contained and sibling procedures
+   or it appears in the uppermost namespace.  */
+
+static int cts = 0;
+static void
+find_derived_types (gfc_symbol *sym, gfc_symtree *st, const char *name,
+		    bool contained)
+{
+  if (st->n.sym && st->n.sym->attr.flavor == FL_DERIVED
+      && !st->n.sym->attr.is_class
+      && ((contained && st->n.sym->attr.use_assoc) || !contained)
+      && gfc_find_component (st->n.sym, name, true, true, NULL))
+    {
+      /* Do the stashing.  */
+      cts++;
+      if (sym->assoc->derived_types)
+	st->n.sym->dt_next = sym->assoc->derived_types;
+      sym->assoc->derived_types = st->n.sym;
+    }
+
+  if (st->left)
+    find_derived_types (sym, st->left, name, contained);
+
+  if (st->right)
+    find_derived_types (sym, st->right, name, contained);
+}
+
+int
+gfc_find_derived_types (gfc_symbol *sym, gfc_namespace *ns, const char *name)
+{
+  gfc_namespace *encompassing = NULL;
+  gcc_assert (sym->assoc);
+
+  cts = 0;
+  while (ns->parent)
+    {
+      if (!ns->parent->parent && ns->proc_name
+	  && (ns->proc_name->attr.function || ns->proc_name->attr.subroutine))
+	encompassing = ns;
+      ns = ns->parent;
+    }
+
+  if (!ns->contained)
+    return cts;
+
+  /* Search the top level namespace first.  */
+  find_derived_types (sym, ns->sym_root, name, false);
+
+  /* Then the encompassing namespace.  */
+  if (encompassing)
+    find_derived_types (sym, encompassing->sym_root, name, true);
+
+  return cts;
+}
+
 /* Find the component with the given name in the union type symbol.
    If ref is not NULL it will be set to the chain of components through which
    the component can actually be accessed. This is necessary for unions because
diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index d63c304661a..bd14ce99ed6 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -3142,6 +3142,10 @@ gfc_conv_variable (gfc_se * se, gfc_expr * expr)
       gcc_assert (se->string_length);
     }
 
+  /* Some expressions leak through that haven't been fixed up.  */
+  if (IS_INFERRED_TYPE (expr) && expr->ref)
+    gfc_fixup_inferred_type_refs (expr);
+
   gfc_typespec *ts = &sym->ts;
   while (ref)
     {
diff --git a/gcc/fortran/trans-stmt.cc b/gcc/fortran/trans-stmt.cc
index e09828e218b..1ec76f9778c 100644
--- a/gcc/fortran/trans-stmt.cc
+++ b/gcc/fortran/trans-stmt.cc
@@ -1747,9 +1747,9 @@ trans_associate_var (gfc_symbol *sym, gfc_wrapped_block *block)
   e = sym->assoc->target;
 
   class_target = (e->expr_type == EXPR_VARIABLE)
-		    && e->ts.type == BT_CLASS
-		    && (gfc_is_class_scalar_expr (e)
-			|| gfc_is_class_array_ref (e, NULL));
+		  && e->ts.type == BT_CLASS
+		  && (gfc_is_class_scalar_expr (e)
+		      || gfc_is_class_array_ref (e, NULL));
 
   unlimited = UNLIMITED_POLY (e);
 
@@ -2043,6 +2043,10 @@ trans_associate_var (gfc_symbol *sym, gfc_wrapped_block *block)
 	{
 	  gfc_conv_expr (&se, e);
 	  se.expr = gfc_evaluate_now (se.expr, &se.pre);
+	  /* Finalize the expression and free if it is allocatable.  */
+	  gfc_finalize_tree_expr (&se, NULL, gfc_expr_attr (e), e->rank);
+	  gfc_add_block_to_block (&se.post, &se.finalblock);
+	  need_len_assign = false;
 	}
       else if (sym->ts.type == BT_CLASS && CLASS_DATA (sym)->attr.dimension)
 	{
@@ -2157,26 +2161,36 @@ trans_associate_var (gfc_symbol *sym, gfc_wrapped_block *block)
 	    {
 	      tree stmp;
 	      tree dtmp;
+	      tree ctmp;
 
-	      se.expr = ctree;
+	      ctmp = ctree;
 	      dtmp = TREE_TYPE (TREE_TYPE (sym->backend_decl));
 	      ctree = gfc_create_var (dtmp, "class");
 
-	      stmp = gfc_class_data_get (se.expr);
+	      if (IS_INFERRED_TYPE (e)
+		  && !GFC_CLASS_TYPE_P (TREE_TYPE (se.expr)))
+		stmp = se.expr;
+	      else
+		stmp = gfc_class_data_get (ctmp);
+
 	      /* Coarray scalar component expressions can emerge from
 		 the front end as array elements of the _data field.  */
 	      if (GFC_DESCRIPTOR_TYPE_P (TREE_TYPE (stmp)))
 		stmp = gfc_conv_descriptor_data_get (stmp);
+
+	      if (!POINTER_TYPE_P (TREE_TYPE (stmp)))
+		stmp = gfc_build_addr_expr (NULL, stmp);
+
 	      dtmp = gfc_class_data_get (ctree);
 	      stmp = fold_convert (TREE_TYPE (dtmp), stmp);
 	      gfc_add_modify (&se.pre, dtmp, stmp);
-	      stmp = gfc_class_vptr_get (se.expr);
+	      stmp = gfc_class_vptr_get (ctmp);
 	      dtmp = gfc_class_vptr_get (ctree);
 	      stmp = fold_convert (TREE_TYPE (dtmp), stmp);
 	      gfc_add_modify (&se.pre, dtmp, stmp);
 	      if (UNLIMITED_POLY (sym))
 		{
-		  stmp = gfc_class_len_get (se.expr);
+		  stmp = gfc_class_len_get (ctmp);
 		  dtmp = gfc_class_len_get (ctree);
 		  stmp = fold_convert (TREE_TYPE (dtmp), stmp);
 		  gfc_add_modify (&se.pre, dtmp, stmp);

[-- Attachment #3: associate_66.f90 --]
[-- Type: text/x-fortran, Size: 1210 bytes --]

! { dg-do run }
! { dg-options "-fdump-tree-original" }
!
! Tests unlimited polymorphic function selectors in ASSOCIATE.
!
! Contributed by Harald Anlauf  <anlauf@gmx.de> in
! https://gcc.gnu.org/pipermail/fortran/2024-January/060098.html
!
program p
   implicit none
!             scalar             array
   associate (var1 => foo1(),    var2 => foo2())
    call prt (var1);   call prt (var2)
   end associate
contains
! Scalar value
   function foo1() result(res)
     class(*), allocatable :: res
     res = 42.0
   end function foo1
! Array value
   function foo2() result(res)
     class(*), allocatable :: res(:)
     res = [42, 84]
   end function foo2
! Test the associate-name value
   subroutine prt (x)
     class(*), intent(in) :: x(..)
     logical :: ok = .false.
     select rank(x)
       rank (0)
         select type (x)
           type is (real)
           if (int(x*10) .eq. 420) ok = .true.
         end select
       rank (1)
         select type (x)
           type is (integer)
           if (all (x .eq. [42, 84])) ok = .true.
         end select
     end select
     if (.not.ok) stop 1
   end subroutine prt
end
! { dg-final { scan-tree-dump-times "__builtin_free" 2 "original" } }

[-- Attachment #4: associate_65.f90 --]
[-- Type: text/x-fortran, Size: 792 bytes --]

! { dg-do run }
! Test fix for PR114141
! Contributed by Steve Kargl  <sgk@troutmask.apl.washington.edu>
program foo
   implicit none
   real :: y
   complex :: z = cmplx(-1,0)
   associate (x => log(cmplx(-1,0)))
      y = x%im  ! Gave 'Symbol ‘x’ at (1) has no IMPLICIT type'
      if (int(100*y)-314 /= 0) stop 1
   end associate

! Check wrinkle in comment 1 (parentheses around selector) of the PR is fixed.
   associate (x => ((log(cmplx(-1,0)))))
      y = x%im  ! Gave 'The RE or IM part_ref at (1) must be applied to a
                ! COMPLEX expression'
      if (int(100*y)-314 /= 0) stop 2
   end associate

! Make sure that IMAG intrinsic is OK.
   associate (x => ((log(cmplx(-1,0)))))
      y = imag (x)
      if (int(100*y)-314 /= 0) stop 3
   end associate
end program

[-- Attachment #5: associate_64.f90 --]
[-- Type: text/x-fortran, Size: 9124 bytes --]

! { dg-do run }
! { dg-options "-fdump-tree-original" }
!
! Tests the fix for PR89645 and 99065, in which derived type or class functions,
! used as associate selectors and which were parsed after the containing scope
! of the associate statement, caused "no IMPLICIT type" and "Syntax" errors.
!
! Contributed by Ian Harvey  <ian_harvey@bigpond.com>
!
module m
  implicit none
  type t
    integer :: i = 0
  end type t
  integer :: i = 0
  type(t), parameter :: test_array (2) = [t(42),t(84)], &
                        test_scalar = t(99)
end module m

! DERIVED TYPE VERSION OF THE PROBLEM, AS REPORTED IN THE PRs
module type_selectors
  use m
  implicit none
  private
  public foo1
contains
! Since these functions are parsed first, the symbols are available for
! parsing in 'foo'.
  function bar1() result(res) ! The array version caused syntax errors in foo
    type(t), allocatable :: res(:)
    allocate (res, source = test_array)
  end
  function bar2() result(res) ! Scalar class functions were OK - test anyway
    type(t), allocatable :: res
    allocate (res, source = test_scalar)
  end
  subroutine foo1()
! First the array selector
    associate (var1 => bar1())
      if (any (var1%i .ne. test_array%i)) stop 1
      if (var1(2)%i .ne. test_array(2)%i) stop 2
    end associate
! Now the scalar selector
    associate (var2 => bar2())
      if (var2%i .ne. test_scalar%i) stop 3
    end associate

! Now the array selector that needed fixing up because the function follows....
    associate (var1 => bar3())
      if (any (var1%i .ne. test_array%i)) stop 4
      if (var1(2)%i .ne. test_array(2)%i) stop 5
    end associate
! ....and equivalent scalar selector
    associate (var2 => bar4())
      if (var2%i .ne. test_scalar%i) stop 6
    end associate
  end subroutine foo1

! These functions are parsed after 'foo' so the symbols were not available
! for the selectors and the fixup, tested here, was necessary.
  function bar3() result(res)
    class(t), allocatable :: res(:)
    allocate (res, source = test_array)
  end

  function bar4() result(res)
    class(t), allocatable :: res
    allocate (res, source = t(99))
  end
end module type_selectors

! CLASS VERSION OF THE PROBLEM, WHICH REQUIRED MOST OF THE WORK!
module class_selectors
  use m
  implicit none
  private
  public foo2
contains

! Since these functions are parsed first, the symbols are available for
! parsing in 'foo'.
  function bar1() result(res) ! The array version caused syntax errors in foo
    class(t), allocatable :: res(:)
    allocate (res, source = test_array)
  end

  function bar2() result(res) ! Scalar class functions were OK - test anyway
    class(t), allocatable :: res
    allocate (res, source = t(99))
  end

  subroutine foo2()
! First the array selector
    associate (var1 => bar1())
      if (any (var1%i .ne. test_array%i)) stop 7
      if (var1(2)%i .ne. test_array(2)%i) stop 8
      select type (x => var1)
        type is (t)
          if (any (x%i .ne. test_array%i)) stop 9
          if (x(1)%i .ne. test_array(1)%i) stop 10
        class default
          stop 11
      end select
    end associate

! Now scalar selector
    associate (var2 => bar2())
      select type (z => var2)
        type is (t)
          if (z%i .ne. test_scalar%i) stop 12
        class default
          stop 13
      end select
    end associate

! This is the array selector that needed the fixup.
    associate (var1 => bar3())
      if (any (var1%i .ne. test_array%i)) stop 14
      if (var1(2)%i .ne. test_array(2)%i) stop 15
      select type (x => var1)
        type is (t)
          if (any (x%i .ne. test_array%i)) stop 16
          if (x(1)%i .ne. test_array(1)%i) stop 17
        class default
          stop 18
      end select
    end associate

! Now the equivalent scalar selector
    associate (var2 => bar4())
      select type (z => var2)
        type is (t)
          if (z%i .ne. test_scalar%i) stop 19
        class default
          stop 20
      end select
    end associate

  end subroutine foo2

! These functions are parsed after 'foo' so the symbols were not available
! for the selectors and the fixup, tested here, was necessary.
  function bar3() result(res)
    class(t), allocatable :: res(:)
    allocate (res, source = test_array)
  end

  function bar4() result(res)
    class(t), allocatable :: res
    allocate (res, source = t(99))
  end
end module class_selectors

! THESE TESTS CAUSED PROBLEMS DURING DEVELOPMENT FOR BOTH PARSING ORDERS.
module problem_selectors
  implicit none
  private
  public foo3, foo4
  type t
    integer :: i
  end type t
  type s
    integer :: i
    type(t) :: dt
  end type s
  type(t), parameter :: test_array (2) = [t(42),t(84)], &
                        test_scalar = t(99)
  type(s), parameter :: test_sarray (2) = [s(142,t(42)),s(184,t(84))]
contains

  subroutine foo3()
    integer :: i
    block
      associate (var1 => bar7())
        if (any (var1%i .ne. test_array%i)) stop 21
        if (var1(2)%i .ne. test_array(2)%i) stop 22
        associate (z => var1(1)%i)
           if (z .ne. 42) stop 23
        end associate
    end associate
    end block

    associate (var2 => bar8())
      i = var2(2)%i
      associate (var3 => var2%dt)
        if (any (var3%i .ne. test_sarray%dt%i)) stop 24
      end associate
      associate (var4 => var2(2))
        if (var4%i .ne. 184) stop 25
      end associate
    end associate
  end subroutine foo3

  function bar7() result(res)
    type(t), allocatable :: res(:)
    allocate (res, source = test_array)
  end

  function bar8() result(res)
    type(s), allocatable :: res(:)
    allocate (res, source = test_sarray)
  end

  subroutine foo4()
    integer :: i
    block
      associate (var1 => bar7())
        if (any (var1%i .ne. test_array%i)) stop 26
        if (var1(2)%i .ne. test_array(2)%i) stop 27
        associate (z => var1(1)%i)
           if (z .ne. 42) stop 28
        end associate
    end associate
    end block

    associate (var2 => bar8())
      i = var2(2)%i
      associate (var3 => var2%dt)
        if (any (var3%i .ne. test_sarray%dt%i)) stop 29
      end associate
      associate (var4 => var2(2))
        if (var4%i .ne. 184) stop 30
      end associate
    end associate
  end subroutine foo4

end module problem_selectors

module more_problem_selectors
  implicit none
  private
  public foo5, foo6
  type t
    integer :: i = 0
  end type t
  type s
    integer :: i = 0
    type(t) :: dt
  end type s
contains
! In this version, the order of declarations of 't' and 's' is such that
! parsing var%i sets the type of var to 't' and this is corrected to 's'
! on parsing var%dt%i
  subroutine foo5()
    associate (var3 => bar3())
      if (var3%i .ne. 42) stop 31
      if (var3%dt%i .ne. 84) stop 32
    end associate

! Repeat with class version
    associate (var4 => bar4())
      if (var4%i .ne. 84) stop 33
      if (var4%dt%i .ne. 168) stop 34
      select type (x => var4)
        type is (s)
          if (x%i .ne. var4%i) stop 35
          if (x%dt%i .ne. var4%dt%i) stop 36
        class default
          stop 37
      end select
    end associate

! Ditto with no type component clues for select type
    associate (var5 => bar4())
      select type (z => var5)
        type is (s)
          if (z%i .ne. 84) stop 38
          if (z%dt%i .ne. 168) stop 39
        class default
          stop 40
      end select
    end associate
  end subroutine foo5

! Now the array versions
  subroutine foo6()
    class(s), allocatable :: elem
    associate (var6 => bar5())
      if (var6(1)%i .ne. 42) stop 41
      if (any (var6%dt%i .ne. [84])) stop 42
    end associate

! Class version with an assignment to a named variable
    associate (var7 => bar6())
      elem = var7(2)
      if (any (var7%i .ne. [84, 168])) stop 43
      if (any (var7%dt%i .ne. [168, 336])) stop 44
    end associate
    if (elem%i .ne. 168) stop 45
    if (elem%dt%i .ne. 336) stop 46

    select type (z => elem)
      type is (s)
        if (z%i .ne. 168) stop 47
        if (z%dt%i .ne. 336) stop 48
      class default
        stop 49
    end select

! Array version without type clues before select type
    associate (var8 => bar6())
      select type (z => var8)
        type is (s)
          if (any (z%i .ne. [84,168])) stop 50
          if (any (z%dt%i .ne. [168,336])) stop 51
        class default
          stop 52
      end select
    end associate
  end subroutine foo6

  type(s) function bar3()
    bar3= s(42, t(84))
  end

  function bar4() result(res)
    class(s), allocatable :: res
    res = s(84, t(168))
  end

  function bar5() result (res)
    type(s), allocatable :: res(:)
    res = [s(42, t(84))]
  end

  function bar6() result (res)
    class(s), allocatable :: res(:)
    res = [s(84, t(168)),s(168, t(336))]
  end

end module more_problem_selectors

program test
  use type_selectors
  use class_selectors
  use problem_selectors
  use more_problem_selectors
  call foo1()
  call foo2()
  call foo3()
  call foo4()
  call foo5()
  call foo6()
end program test
! { dg-final { scan-tree-dump-times "__builtin_free" 18 "original" } }

[-- Attachment #6: Change99065.Logs --]
[-- Type: application/octet-stream, Size: 3094 bytes --]

Fortran: Fix class/derived/complex function associate selectors [PR87477]

2024-03-03  Paul Thomas  <pault@gcc.gnu.org>
	    Steve Kargl  <sgk@troutmask.apl.washington.edu>

gcc/fortran
	PR fortran/87477
	PR fortran/89645
	PR fortran/99065
	PR fortran/114141
	* class.cc (gfc_change_class): New function needed for
	associate names, when rank changes or a derived type is
	produced by resolution
	* dump-parse-tree.cc (show_code_node): Make output for SELECT
	TYPE more comprehensible.
	* gfortran.h : Add 'gfc_association_list' to structure
	'gfc_association_list'. Add prototypes for
	'gfc_find_derived_types', 'gfc_fixup_inferred_type_refs' and
	'gfc_change_class'. Add macro IS_INFERRED_TYPE.
	* match.cc (gfc_match_associate): Eliminate parentheses from
	selector expression except for variables.
	(copy_ts_from_selector_to_associate): Add bolean arg
	'select_type' with default false. If this is a select type name
	and the selector is a inferred type, build the class type and
	apply it to the associate name.
	(build_associate_name): Pass true to 'select_type' in call to
	previous.
	* parse.cc (parse_associate): If the selector is a inferred type
	the associate name is too. Make sure that function selector
	class and rank, if known, are passed to the associate name. If
	a function result exists, pass its typespec to the associate
	name.
	* primary.cc (gfc_match_varspec): If a scalar derived type
	select type temporary has an array reference, match the array
	reference, treating this in the same way as an equivalence
	member. If this is a inferred type with a component reference,
	call 'gfc_find_derived_types' to find a suitable derived type.
	If this is an inquiry reference, the target expression is
	permissable and can be resolved and the primary expression must
	be complex for re and im references.
	* resolve.cc (resolve_variable): Call new function below.
	(gfc_fixup_inferred_type_refs): New function to ensure that the
	expression references for a inferred type are consistent with
	the now fixed up selector.
	(resolve_assoc_var): Ensure that derived type or class function
	selectors transmit the correct arrayspec to the associate name.
	(resolve_select_type): If the selector is an associate name of
	inferred type and has no component references, the associate
	name should have its typespec.
	* symbol.cc (gfc_set_default_type): If an associate name with
	unknown type has a selector expression, try resolving the expr.
	(find_derived_types, gfc_find_derived_types): New functions
	that search for a derived type with a given name.
	* trans-expr.cc (gfc_conv_variable): Some inferred type exprs
	escape resolution so call 'gfc_fixup_inferred_type_refs'.
	* trans-stmt.cc (trans_associate_var): Tidy up expression for
	'class_target'. Correctly handle selectors that are class
	functions and class array references, passed as derived types.

gcc/testsuite/
	PR fortran/87477
	PR fortran/89645
	PR fortran/99065
	* gfortran.dg/associate_64.f90 : New test
	* gfortran.dg/associate_66.f90 : New test

	PR fortran/114141
	* gfortran.dg/associate_65.f90 : New test